Bedrift I - Harstad
- Industrimontasje AS
- Idrive AS
- iHarstad
- iTet AS
- Iamme AS
- Ingeniørkompaniet ANS
- Informatics AS
- Imalo AS
- Inspiranor Tennbakk
- Irene Sørensen
- Iver Jensa AS
- Ingebyre Omotony
- Ibestad Pinsemenighet
- Ingar Aspevoll
- iteam Harstad
- Imants Bite
- Ibestad Pinsemenighet
- Igor Grushyn
- Ida Grindahl
- If Skadeforsikring
- Inko Eiendom AS
- Idrive Harstad
- Inko Holding AS
- Innaførr Harstad AS
- Inventum Copysafe
- Ident Tannteknikk AS
- Iro Invest AS
- Into Eiendom AS
- Isabell Olsen
- Isabell Olsen
- Ip Care AS
- Ingvild Strand
- Inge Jensa AS
- Imtas Harstad AS
- IMTAS Harstad
- Intex Vedlikehold
- Intersport Kanebogen
- Iselin Evensen
- Isotec Harstad AS
- Ik Hind
- IF Kilkameratene
- Isaksen Marthe
- Isaksen Byggeservice
- IKM Teknor AS
- Ingebrigtsen Britt
- Ingebrigtsen Anne Mari
- Ingeborg Berg Nilssen
- Ib Maler Proff AS
- Inga Helene Juul
- Id Oddlaug Skardal
- Ing. Geir Søreng
- Isaksen Tove Annie
- Irene Sanchez Briongos
- Isabel Bruun Holding AS
- Industriveien 12 Andenes AS
- ISS Facility Service
- Idar Jarle Brendmo
- Intunor Services AS avd Harstad
- Inger Alvilde Ingemann
- Industri og Anlegg AS
- Independent MC Harstad
- I-A Holding AS
- Industri & Maling AS
- Industri & Maling AS
- ISS Facility Services AS
- Ingunn Jensen Bunadssøm
- Inge Bernt Olsen
- Imtas Harstad 2 AS
- Inger Johanne Dybwad
- Ingeniør Torgeir Hardersen
- IKM Karsten Moholt AS
- Ingeborgsh Ingeborg Sandlien Halseth
- International Students Union Hih
- Ingeborg Annie Sivertsen Lindahl
- Inko Industri- og Kompetansesenter AS
- Interesseforeningen for Radio Harstad
- Interflora Troms Nordnorsk Blomsterhandlerforening
- Ingunn Ågot Sundgaard Holtan
- I - Hus V/ Stig Ivetorp
- ISS Service Management AS Avd Renhold Harstad
- Inko AS Avd Vta Harstad Storgt 41
- IT Partner Harstad AS (Serit Hålogaland)
- Industri Energi Equinor - Avdeling Harstad
- Ingrid Fysioterapi og Drill Ingrid Mørch Lind